The banks of Timber Creek, in early historic times, were thickly forested with white oaks, bur oaks, and sugar maple trees. The white oak became the state tree of Illinois, while the sugar maples were used by local Illini Native Americans to make springtime maple syrup and maple sugar.
Maple sweetening was highly prized among early Euro-American settlers, and as early as 1824 Isaac Funk settled here. The Funk family began to sell sirup commercially in 1891, and the family continues to control and harvest much of the grove as of 2008.
Due to fire suppression, the makeup of tree life in Funk's Grove is changing from historic times, with the original oaks not reproducing themselves naturally.
Funks Grove continues to be a favorite landmark for users of historic U.S. Route 66, which is signed in McLean County as it passes through the grove. In addition, a rest stop lies on the edge of the grove on Interstate 55 at Illinois Milepost 149. The rest stop contains some memorabilia of the grove.